Anyone who has seen Star Trek: Next Generation has fantasized about stepping into the virtual reality structure known as the “holodeck” and taking a vacation from the real world. And while the visual component has a long way to go, the AI that would control the characters you interact with in that environment is coming along quite nicely. That’s according to researchers and developers Michael Mateas and Andrew Stern.
Stern was at GDC Thursday morning to present his and Mateas’ paper “Facade: An Experiment in Building a Fully-realized Interactive Drama.” He notes that he quit his job in the game industry to dive into interactive story development with Mateas. “Three years later, interactive story kicked our asses,” he quips.
What they have ended up with so far is a first-person dramatic experience about relationships where the player engages with AI characters through direct, continuous dialogue, gestures and actions in 3D space. The hilarious video demo featured rudimentary 3D animation which places the player at an awkward dinner party where the host couple is on the verge of a break-up. By typing in bits of random dialogue, the player engages Grace and Trip, and alters the fate of their relationship. At one point, Grace comments on how she dislikes a painting on the wall. The player typed in, “Yeah. It kinda sucks.” The remark triggered agreement from Grace and defensiveness from Trip, who loves the painting.
So how does it work? The AI processes the players’ dialogue and generates Grace’s and Trip’s verbal and non-verbal reactions by plucking 60-second story beats from a vast pool. To make the characters come to life, Stern and Mateas created A Behavior Language (ABL), which makes Grace and Trip capably of multi-intelligent activities composed from a large collection of parallel sequential and joint behaviors. ABL will be made publicly available around 2004.
Stern says the main challenge was figuring out how to create a coherent story while giving the player freedom to do whatever he/she wants. What they have succeeded in doing is creating an AI architecture to support character/story integration and a drama manager that sequences story pieces – a technique for moving beyond tree plot structures. The have also produced the first published, integrated interactive drama architecture described in enough detail that it can be implemented.
They are still working on giving the experience more story beats to bridge character and plot, making the player more of a protagonist rather than an equal participant, giving characters a more symmetrical range of expression and eliminating non-understood utterances and false positives.
Among their successes, Stern and Mateas count creating a prototype of the “real thing.” If things pan out the way they hope, they could be on the verge of revolutionizing the game industry an taking us one step closer to virtual vacations – Starship Enterprise-style.